Clamping device



CLAMPING DEVICE Filed Apfil 23, 1941 2 Sheets-Sheet l" Rv O W ATTORNEY.

2 Sheets-Sheet 2 G. P. RINKER :TAL

Dec. 29; 1942.

I CLAMPING DEVIC'JE.

Filed. ARril '25, 1941 Patented Deo. 29, 1942 CLAMPIN G DEVICE George Paul Rinker, Brooklyn, and Russel Parry Miller, Indianapolis, Ind., assignors to Line Ma`. terial Company, MilwaukegWisi., a corporation of Delaware Application (April 23, 1941, Serial No. 389,902

6 Claims.

This invention relates to devices for releasably gripping and holding under tension a steel cable or the like; and it has for its principal object to provide a device of that character which will grip a cable more securely but with less tendency to injure the cable than other devices of its kind heretofore employed.

Another object is to provide a device of the above description which is capable of use with cables having a substantial range of diameters without the necessity of employinga different set of jaws for each size of cable.

The novel features of our invention can be indicated most readily in conjunction with the drawings and detailed description which follows:

In the drawings:

Fig. 1 is an elevational View, partly in section, depicting a releasable cable-gripping and holding device in accordance with a preferred embodiment of our invention-the device being illustrated in gripping engagement with a cable and attached to a fixed support, r

Fig. 2 is a top plan view, of the device.

Figs. 3 and 4 show the gripping surfaces of the jaws shown in Fig. 1. v

Fig. 5 is an enlarged sectional View taken on the line 5-5 of Fig. 1.

Identical parts are designated by the same reference numerals throughout the several views.

The clamping device illustrated includes a link member IU pivotally secured to an eye-bolt I3 by means of a pin I4 which is held in place by a cotter pin I5. f

. Eye-bolt I3 is secured to any suitable support,

as for example an electric transmission pole I6..

fragmentarily shown.l

Link member I0 is formed, intermediately of its ends with a hook I8 for purposes hereinafter explained.

A jaw-supporting element includes a pair of spaced side members 2| disposed in mutually parallel relationship and joined by a kcross-rib 22 which is cast integrally with the side members.

Said jaw-supporting element is pivotally connected to link I0 by means of a pin 24 which is locked in place by a cotter pin 24A.

A jaw 29 is pivotally connected to the jawsupporting element by means of a pivot pin 21; and a jaw 30 is similarly connected to said element by means of a pin 28. The two jaws are rotatable about their respective pivots.

Jaw 29 has a reinforcing web 35 and is formed at one end to provide a cable-guide channel 33- which is dened by two spacedv complementary iianges 34. The upper end of the said jaw 29 has an elongated cable-gripping surface 3| which is convexly arcuate in al plane transverse to the axis of pivot pin 2l, as shown in Fig. l-said surface being concave in cross section as illustrated in Fig. 5. The cable-gripping surface of jaw 29 merges into cable-guide channel 33 and forms a continuation thereof. Jaw 3 has a reinforcing web 39 and has an elongated cable-gripping surface 3l which is concavelyV arcuate in a plane transverse to the axis of pivot pin 28, as shown in Fig. 1-said surface 3l being concave in cross section as illustrated in Fig- 5.

The two cable-gripping jaw surfaces 3l ad 3l are mutually in face-to-face relation and are approximately parallel when engaging a cable as shown. The two jaw surfaces define, conjointly, a'channel substantially embracing the cable 42 and the two jaws function conjointly to grip the cable when tension'is applied to the cable in the direction indicated by arrow A, Fig.V 1.

If the two jaws are rotated in a clockwise direction, as viewed in Fig. 1, their respective cablegripping surfaces will'separate to a limited extent. Likewise, if said jaws are rotated in a counter-clockwise direction as Viewed in Fig. 1, the cable-gripping surfaces will move toward each other. Hence, vit will be apparent that the device is capable of use with cables having a substantial range of v diametersalthough not adapted, with a single pair of jaws, for use with cables of widely varying diameters.

Y The cable-gripping surfaces 3| and 3l. are preferably provided with angularly extending grooves 32 and 38 in approximate conformity .Y with the yangularly extending strands of the` 'I'he cable strands tend to'seat themselvesr in said grooves, thereby increasingl ,the

cable.

f grip of the jaws on the cable.

It will be apparent that when tension is applied to the cable, as indicated, jaw 29 will be rotated about its pivot in a manner tending'to close the gap between the two cable-gripping surfaces and that the cable will be gripped between the jaws along a surface of considerable rlength-instead of beingr gripped at a single pin 21 to the projected axis of the tensioned portion of the cable, the greater will be the moment of force for a given applied tension and, corre-A spondingly, the greater willV be the gripping force applied to the cable. For that reason jaw 29, as shown, is considerably longer from its pivotal center to the cable-guide end than from the pivotal center to the other end. This is not essential to the operativeness of the device, but it contributes greatly to the effectiveness of the jaws to provide for an ample moment of force. Manifestly, it is not of the essence of the invention that jaw 29 be asymmetrical, as shown in Fig. 1.

If the device is applied to a smaller cable than that shown, the jaws will rotate counterclockwise, as viewed in Fig. 1, in order to adjust themselves to the smaller cable, and that results in a diminution of the lever arm and a consequent diminution of the moment of force-if a given cable tension is assumed. But an increase in the diameter of the cable will have the opposite effect. In designing a device in accordance with this invention, the aforementioned factors should be kept in mind.

Link I is not an indispensable element, but it serves as a convenient means for adequately spacing the jaws from the xed support I6 and also as a convenient means for attaching a block and tackle. In connecting the cable to our gripping and holding device it is the usual practice to attach to the cable, temporarily, a suitable clamp to which one end of the block and tackle can be fastened, and the other end of the block and tackle is connected to hook I8. The cable is then put under tension by means of the block and tackle and the loose end 43 of the cable is threaded between jaws 2S and 3l); and a man throws his weight on the dependent cable end while the block and tackle is being released. Tension of the cable then automatically causes jaw 29 to rotate and gripping engagement of the cable between the jaw surfaces is immediately eiected.

The point of attachment of the jaw-supporting element to the fixed support which, in the case illustrated, is pin 24, should be remote and laterally displaced from a plane parallel to and intersecting the axes of the two pivot pins 21 and 2li-in order to obtain adequate leverage on jaw 29. This rule is applicable, of course, only Whenthe jaw-supporting element is pivotally connected to its support as here depicted. Manifestly, the pivotal attachment makes it possible to run the cable at any desired angle to the xed support, which, obviously, would not hold true if the jaw-supporting element were rigidly mounted.

When it is found to be desirable to change the size of wire or cable on an electric transmission line, or remove the cable 42 for any reason from its gripped position, the removal is easily and quickly accomplished by reversing the mounting operation hereinbefore described. A block and tackle is attached to the cable and hook I8 and the tension relieved from the jaws, thereby enabling the operator to remove from place the cotter pin 45, pin 21, and jaw 29. In this manner the cable is quickly and easily lowered without interference from the jaws which if in place would tend to grip the cable during the removal operation.

From the foregoing description it is obvious thatv the objects of this. invention have been accomplished by providing a. clamping. device having pivotally mounted, removable jaws automatically coacting to provide a uniform grip on a cable held therebetween and to provide a quick and simple manner of connecting and disconnecting a cable therewith.

Further objects have been accomplished by providing jaws relatively pivoted with respect to the direction of cable pull so as to be rotated into a plurality of various cable openings whereby various size cables may be effectively held without the angle of the jaws ato the direction of wire pull being changed enough to prevent gripping.

We claim:

1. In a device for releasably gripping and holding under tension a cable or the like, the combination comprising a jaw-supporting element, a pair of co-operating clamping jaws pivotally connected to said element and carried thereby, the pivotal axes of said jaws being parallel and spaced apart laterally, each of said jaws having an elongated cable-gripping surface which is arcuate in a plane transverse to its pivotal axis, one of said surfaces being convexly arcuate in said plane, the other of said surfaces being concavely arcuate in said plane, said surfaces being spaced apart laterally and disposed mutually in face-to-face relation, the elongated arcuate contours of said surfaces being approximately parallel when a cable or the like is gripped therebetween.

2. In a device for releasably gripping and holding under tension a cable or the like, t'he combination comprising a jaw-supporting element and a pair of cable-gripping jaws carried by said element, at least one of said jaws being movable relatively to the other for gripping and releasing a cable therebetween, said jaws having elongated cable-gripping surfaces which are of arcuate contour lengthwise of the cable-portion therebetween, said surfaces being complementarily convex and concave respectively, said device including cable-actuated lever means for pressing said surfaces into conjoint gripping engagement with the cable, said lever means being responsive to tension applied to the gripped cable to eiect and vary proportionately to said tension, the tenacity of said gripping engagement.

3'. In a device for releasably gripping and holding under tension a cable or the like, the combination comprising a jaw-supporting element and a pair of cable-gripping jaws carried by said element, at least one of said jaws being movable relatively to the other for gripping and releasing a cable therebetween, said jaws having cooperative cable-gripping surfaces which are elongated lengthwise of the cable-portion gripped therebetween and operative to grip the cable throughout an elongated area, said device including lever means operable by the cable gripped between said surfaces to effect cable-gripping actuation of said device in response to tension applied to said cable and further operative to vary proportionately to the tension applied to said cable the tenacity of the grip of said jaws on the cable.

4. In a device for releasably gripping and holding under tension a cable or the like, the combination comprising a jaw-.supporting element, a pair of co-operating clamping jaws pivotally connected to said element and carried thereby, the pivotal axes of said jaws being parallel and spaced apart laterally, each of said jaws having an elongated cable-gripping surface which is arcuate in. a plane transverse to itspivotal axis and concavely grooved in a plane normal to its length, one of said surfaces being convexly arcuate in said mst-mentioned plane, the other of said surfaces being concavely arcuate in saidk connected to said element and carried thereby, the pivotal axes of said jaws beingY parallel and spaced apart laterally, each of said jaws having an elongated cable-gripping surface which is arcuate in a plane transverse to its pivotal axis, one of said surfaces being convexly arcuate in said plane, the other of said surfaces being concavely arcuate in said plane, said surfaces being spaced apart laterally and disposed mutually in face-to-face relation, the elongated arcuate contours of said surfaces being approximately parallel when a cable or the like is gripped therebetween, a coupling pin carried by said jaw-supporting element, the axis of said coupling pin `pair of co-operating clamping jaws pivotally being parallel to the pivotal axes of said jaws and displaced laterally from a plane intersecting the pivotal axes of said jaws, said coupling pin being adapted for connecting said element to a supporta 6. YIn a device for relea'sable gripping and holding under tension a cable or the like, the combi-v nation comprising a .jaw-supporting element, a pair of cooperating clamping jaws pivotally connected to said element and carried thereby, the pivotal axes of said jaws 'being parallel and spaced apart laterally, each of said jaws having an elongated cable-gripping surface which is arcuate in a plane transverse to its pivotal axis, one of said surfaces being convexly arcuate in said plane, the other of said surfaces being concavely arcuate in said plane, said surfaces being `spaced apart laterally and disposed mutually in face-to-face relation, the elongated arcuate contours of said surfaces being approximately parallel when a cable or the like is gripped therebetween, and a supporting linlrhaving one end pivotally connected to said element at a point laterally displaced and remote from a plane parallel to and intersecting the pivotal axes of saidvjaws, the other end of said link being arranged for connection to a fixed support.

GEORGE PAUL RINKER. RUSSEL PARRY MILLER. 

